1. Field of the Invention
The present invention relates to a dental crown material and a dental crown used for dental treatment.
2. Description of the Prior Art
Conventionally, an alloy material such as a silver-palladium alloy, a nickel-chromium alloy and a cobalt-chromium alloy, and a metal material in which a ceramic material is fused, are used as dental crown materials. The alloy material is conveniently formed into a dental crown by a lost wax process.
When the alloy material is used in the oral cavity of a patient for a long period of time, however, a toxic metal element such as chromium, cobalt, or cadmium may elute from the alloy and be accumulated in the patient's body. In addition, since the alloy material has a high thermal conductivity and thus the difference in thermal conductivity between a crown made by the alloy material and a natural tooth is large, when the patient eats food having a large temperature difference from the body temperature, he may often experience discomfort.
Since a crown formed by a metal material containing a fused ceramic material is too hard, it creates wear on the opposing tooth. Also, its color is not natural compared to that of a natural tooth, and its moldability is poor.